Note: Descriptions are shown in the official language in which they were submitted.
~2~
Method to produce a container
The invsntion relates to a method to produce a
container, such as for example a can or tube, for the
accommodation of a ~illing material, in which case, after
production of the container, its interior is primed.
Hitherto, cans, for example, have been produced
by pressing, deep drawing or the like. After production
they are cut and washed and subsequently dried. Then an
insids protective lacquer is customarily sprayed on, to
be precise, to a thickness of approximately 5-8~ which,
in turn, i9 dried. The disadvantage lies in the fact
that cans or tubes of this type are not resistant to
aggressive filling materials.
The inventor's aim was to develop a method of the
abovementioned type, in which a container is provided
whichhas this re~istance to aggressive filling materials,
and in which, additionally, any seams present are sealed
off.
This object is achieved in that a coa~ing with a
layer thickness of 30-70~ is applied on the prLmer.
- This relatively thick coating is suitable, above
all, for containers for the accommodation of aggressive
filling matarials. These containers can be tubes or also
aluminum cans. Furthermore, the coating is al~o suitable
for white ~in cans since the seam generally present in
white tin cans is sealed by the coating~ Howe~er, the
coating is also likewise well-suited for plastic cans.
Incidentally, the primer generally has a layer
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thickness of 20-30~ with the result that a total layer
thickness of primer and coating of approximately 50-100
results.
For the coating, polyolefins or similar sub-
stances are suita~le, or example, as well a~ mixtures of
polyole~ins and other substances. This has the essential
advantage that polyolefins burn when the container is
recycled, without polluting -the environment. However,
the coatin~ can also consist of a poly~thylene or of
other plastics. No limits are to be placed on the
innovative concept in this case.
Subsequently, the container is placed in a drying
oven and sub~ected to heat of 160-190C. Then the
container is preferably cooled down to 40-50C.
The external treatment of the container is
effected by applying a special ~ingle-component basic
lacquer which can be dried at low temperatures in ordex
to avoid damaging the inside coating. A covering lacquer
is then applied.
- Incidentally, such a coating according to the
invention is also suitable for a valve lid to be placed
on the can at a later point in time. It is used, above
all, for aerosol cans.
